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Synastry vs composite chart: compatibility explained
SoulMetric Team · June 15, 2026
Relationship astrology usually starts with two techniques: synastry (chart overlay) and composite (midpoint chart). SoulMetric Match uses both western synastry and Human Design composite charts.
Synastry: two charts overlaid
Synastry compares Planet A in one chart to Planet B in the other. Classic patterns:
- Sun–Moon contacts — emotional recognition
- Venus–Mars contacts — attraction chemistry
- Saturn contacts — commitment and friction
Synastry excels at naming where ease and tension show up — attraction, communication, pacing.
Composite: the relationship as its own chart
A composite chart calculates midpoints between two natal charts to describe the relationship entity itself — its purpose, stress points, and growth edges.
Composite is not "better" than synastry; it answers a different question: What is this bond trying to become?
Human Design composite in SoulMetric
Human Design adds a composite bodygraph — how your combined energy operates. On Seeker+, SoulMetric Match shows bond archetype headlines, synastry zone bars, and HD composite depth.
Oracle tier adds Discuss with Luna about any pairing.
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Last updated: June 21, 2026